Abstract

Application programmers increasingly prefer distributed stor-age systems with strong consistency and distributed transac-tions (e.g., Google’s Spanner) for their strong guarantees and ease of use. Unfortunately, existing transactional storage sys-tems are expensive to use – in part because they require costly replication protocols, like Paxos, for fault tolerance. In this paper, we present a new approach that makes transactional storage systems more affordable: we eliminate consistency from the replication protocol while still providing distributed transactions with strong consistency to applications. We present TAPIR – the Transactional Application Proto-col for Inconsistent Replication – the first transaction protocol to use a novel replication protocol, called inconsistent repli-cation, that provides fault tolerance without consistency. By enforcing strong consistency only in the transaction protocol, TAPIR can commit transactions in a single round-trip and or-der distributed transactions without centralized coordination. We demonstrate the use of TAPIR in a transactional key-value store, TAPIR-KV. Compared to conventional systems, TAPIR-KV provides better latency and throughput. 1.